Large diameter pipe strings are extensively used in the search for and production of oil and gas lying below the sea. These pipe strings, used with an offshore drilling vessel or platform, are typically made up of joints of pipe which are up to 60 feet in length and 36 inches in outer diameter. The length of the combined string can range from hundreds to thousands of feet.
Adjacent joints of pipe are typically threadedly engaged by helical threads or by interrupted threads of the lead or no lead type.
Because of the extreme conditions experienced by the pipe strings, it is highly advantageous to provide a locking mechanism preventing disconnection of the couplings of adjacent joints of pipe. It is also highly advantageous to provide a mechanism for remotely releasing such connection to avoid sending a diver into the water.
Examples of such remotely releasable connectors are disclosed in U.S. Pat. Nos. 3,100,655 issued to Work; 3,339,947 issued to Maisey; 3,895,829 issued to Manson; and 3,948,545 issued to Bonds.
While the mechanisms disclosed in these patents provide a remote release of the connection, they are not extremely reliable and are extremely complicated to manufacture. Thus, there has been a continuing need for improvement in remotely releasable connectors for, e.g., underwater well pipe.